The present invention relates to monitoring and control of a froth flotation plant.
In a flotation plant for mineral ores the flow of a mineral mixture to be processed has to be observed and controlled in order to achieve optimum separation of its constituents. For this purpose froth speed, bubble size and stability are important factors.
Since the early days of flotation, process technicians have known that the speed at which the froth is recovered over the lip of a flotation cell has a very direct and consistent influence on the grade and recovery of the circuit. One of the most important aspects of a process technician""s job is ensuring is that the froth is moving at a desired and controlled speed over the lip. Unfortunately, process technicians cannot watch the froth throughout an entire shift, as there are always other problems to attend to.
A considerable amount of work has been done in order to improve control of flotation, for instance by automatically measuring the speed of the froth. This measurement would then be used in simple controllers to emulate the steps taken by the process technician in correcting deviations of the froth speed from its desired level. Many of the earlier attempts to measure speed were ineffective, as they were unable to cope with turbulence of the froth surface.
It is an object of the invention to suggest monitoring and control means, which will result in improved monitoring and control of a froth flow in a flotation plant.
According to the invention, there is provided a monitoring arrangement for a froth flotation cell of a flotation plant, which arrangement includes an optical observation means adapted to observe digitally a series of images to extract froth characteristics in a mineral mixture flow in a froth flotation cell of a flotation plant and being further adapted to emit corresponding digital image signals; a computer for processing digital image signals received from the optical observation means and being adapted to emit parameter signals of calculated parameters of froth characteristics; digital image transmitting means adapted for transmitting digital image signals from the optical observation means to the computer; display means for displaying parameter signals received from the computer; and parameter signal transmitting means adapted for transmitting parameter signals from the computer to the display means.
Also according to the invention, there is provided a monitoring and control arrangement for a froth flotation cell of a flotation plant, which arrangement includes an optical observation means adapted to observe digitally a series of images to extract froth characteristics in a mineral mixture flow in a froth flotation cell of a flotation plant and being further adapted to emit corresponding digital image signals; a computer for processing digital image signals received from the optical observation means and being adapted to emit parameter signals of calculated parameters of froth characteristics and being further adapted to produce control signals in response to parameter signals received for causing required variations in froth characteristics in a froth flotation cell; digital image transmitting means adapted for transmitting digital image signals from the optical observation means to the computer; control means for controlling froth characteristics in a froth flotation cell; and control signal transmitting means adapted for transmitting control signals from the computer to the control means for causing required variations in froth characteristics in a froth flotation cell.
Further according to the invention, a monitoring and control arrangement for a froth flotation cell of a flotation plant arrangement includes an optical observation means adapted to observe digitally a series of images to extract froth characteristics in a mineral mixture flow in a froth flotation cell of a flotation plant and being further adapted to emit corresponding digital image signals; a computer for processing digital image signals received from the optical observation means and being adapted to emit parameter signals of calculated parameters of froth characteristics and being further adapted to produce control signals in response to parameter signals received for causing required variations in froth characteristics in a froth flotation cell; digital image transmitting means adapted for transmitting digital image signals from the optical observation means to the computer; display means for displaying calculated parameter froth characteristic signals received from the computer; parameter signal transmitting means adapted for transmitting parameter signals from the computer to the display means; control means for controlling froth characteristics in a froth flotation cell; and control signal transmitting means adapted for transmitting control signals from the computer to the control means for causing required variations in froth characteristics in a froth flotation cell.
Yet further according to the invention, a method of monitoring a mineral mixture flow in a froth flotation cell of a flotation plant includes the steps of obtaining a series of digital images extracted of froth characteristics from a flotation cell of a flotation plant; of transmitting the digital images to a computer for processing thereof; of processing the digital images in the computer into parameter signals of digital parameter froth characteristics; and of transmitting the parameter signals to a display means for displaying the digital parameter froth characteristics obtained.
Further according to the invention, a method of monitoring and controlling a mineral mixture flow in a froth flotation cell of a flotation plant includes the steps of obtaining a series of digital images extracted of froth characteristics from a flotation cell of a flotation plant; of transmitting the digital images to a computer for processing thereof; of processing the digital images in the computer into parameter signals of digital parameter froth characteristics; of producing control signals in response to parameter signals received for causing required variations in froth characteristics in a froth flotation cell; and of controlling the froth characteristics in the flotation cell in response to the control signals so as to cause required variations in the froth characteristics in the cell.
Further according to the invention, a method of monitoring and controlling of a mineral mixture flow in a froth flotation cell of a flotation plant includes the steps of obtaining a series of digital images extracted of froth characteristics from a flotation cell of a flotation plant; of transmitting the digital images to a computer for processing thereof; of processing the digital images in the computer into parameter signals of digital parameter froth characteristics; of transmitting the parameter signals to a display means for displaying the digital parameter froth characteristics obtained; of producing control signals in response to parameter signals received for causing required variations in froth characteristics in a froth flotation cell; and of controlling the froth characteristics in the flotation cell in response to the control signals so as to cause required variations in the froth characteristics in the cell.
Froth characteristics may be selected from a group including froth speed, froth stability and bubble size.
The parameter signals transmitted from the computer may be converted to an analog industrial standard or to a digital industrial standard.
The calculated parameter signals transmitted from the computer may be converted to an analog or digital industrial standard, like 4-20 mA, 0-10V, or Fieldbus (for example Profibus or Modbus).